1. This question concerns the basic structures used within Z specifications. (a) Does the formula Vx: N. (x* x > X) of first-order logic evaluate to true? Justify your answer. (b) Let S = {1,2,3,4} and T = {a,b,c} as well as f = {1a, 2b, 3c, 4 a} and g={1+b, 2 a, 3 c}. [5 marks] [4 marks] Determine for f and g whether or not they are injections from S to T. Justify your an- swers. (c) Give a total surjection from the set {..., 4, -2, 0, 2, 4, ...} of even integers to the set {0, 1, 2,...} of natural numbers. Justify your answer. [6 marks]